Lithium ion batteries that operate at voltages higher than a single cell can provide are generally comprised of multiple cells. Lithium ion battery cells may function non-optimally when subjected to an over-voltage or under-voltage condition due to overcharging or undercharging. Over a life of a battery, a battery cell may develop an internal leakage resistance mismatched higher or lower relative to other battery cells. Over time, the mismatch in leakage current may cause one or more battery cells to become overcharged or undercharged. Overcharging a battery cell may result in a non-optimal condition due to high cell temperature that may result in non-optimal operation of the cell. Discharging the battery cell to zero volts or zero amp-hours of stored energy may make the battery cell inoperative.